I'm thinking the xrite colorchecker passport is useless after reading this...

I think the checker passports are a specialist tool for people who NEED to get colours accurate. Real estate, product photography etc then it makes sense. Stage your shot, shoot the passport,  then get on with the rest of the job. It doesn't make sense for weddings, run and gun or any "artistic" shots where the colour isn't super important. For anybody who has a specialist need for accurate colour, the passport is a great tool and using "neutral" or whatever isn't going to suffice. For the 99% of us who DON'T need 100% accurate colour, the checker isn't necessary.

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